Cut the tuna into thin slices.
Heat a griddle pan until very hot. Season and oil the tuna and then sear for 30 seconds on each side.
Soak the bread in a little water. Peel the garlic and crush with a pinch of salt. De-seed and dice the tomatoes, cucumber, pepper and the chilli. Pick the basil leaves from the stalks, retaining some of the small leaves for garnish. Blend all of your ingredients with the oil and vinegar and season to taste. Pass through a sieve and leave to chill thoroughly in the fridge.
Pour the chilled soup into a shallow bowl. Place the tuna in the middle and garnish with and basil leaves.
«Prepare this soup the day before. This will improve the flavour and make your dinner party much easier.»